In view of the need to reduce manufacturing costs, space occupied and total weight, which is particularly pressing in the field of motorcar manufacture, there is strong demand to reduce the number of fluid-circulation adjustment and control elements in complex circuits and if possible to incorporate all the adjustment and control functions in one operational and structural assembly, operated by one actuator, thus producing one adjustment unit for a plurality of circuit portions of the same general circuit.
Another possible way of reducing costs consists in fitting actuators that are cheap to manufacture and therefore uncomplicated and of a simple structure.
A twofold problem therefore emerges, namely, that of spatially connecting the various circuit portions inside the unit (problem of overall size) and that of achieving different adjustments for the various circuit portions while respecting their hierarchy and the conditions whereby they are achieved, based on the general adjustment within the circuit as a whole.
The above-mentioned problems arise principally with regard to the adjustment, by means of a structural device or single module, of the circulation of coolant within a circuit comprising a main portion and at least two, preferably three, secondary portions, namely, for example, not only the circuit running through the engine block, but also a loop passing through a radiator, a loop passing through a unit heater, and possibly a by-pass loop.
The problem facing the present invention therefore basically consists in providing a multi-way adjustment device that requires only a simple means of actuation, for example by translation, comprising only one adjustment element and enabling connections in at least two perpendicular directions.